Trans electronic structures

A. Klein, E.J.L. Mclnnes, T. Scheiring and S. Zalis, Electronic structure of radical anionic binuclear organoplatinum complexes. A multiple frequency EPR investigation, J. Chem. Soc., Faraday Trans., 1998, 94, 2979. 

For a more detailed understanding of the electronic structure of these complexes see Green, C. J. Suter, J. L. J. Chem. Soc., Dalton Trans. 1999, 4087. 

Lennard-Jones, J. E. "The Electronic Structure of Some Diatomic Molecules." Trans.Far.Soc. 25 (1929) 668682. 

Qiu Guanzhou, Yu Runlan, Hu Yuehua, Qin Wenqing, 2004. Corrosive electrochemistry of jamesonite. Trans. Nonferrous Met. Soc. China, 14(6) 1169- 1173 Qiu Guanzhou, Xiao Qi, Hu Yuehua, 2004. First-principles calculation of the electronic structure of the stoichiometric pyrite FeS2(100) surface. Computation Materials Science, 03-11 ... 

Comparisons between the electronic structures (using a ZINDO analysis) of [Ru(bpy)3] " and [Ru(bpy)(NH3)4], and between related pairs of compounds where bpy is replaced by 2,2 -bipyrazine or 1,2-benzoquinonediimine, show that bpy is unable to accept extra electron density from the metal center whereas the opposite is true for 1,2-benzoquinonediimine. The acceptor properties of the 2,2 -bipyrazine ligand fall between those of bpy and 1,2-benzoquinonediimine. Using the Fenske-Hall method, the electronic structures of [Ru(bpy)3 (ppy) ] "A (Hppy = 2-phenylpyridine) have been investigated. The coordinated ppy is a C,A-donor. The electronic structures of the heteroleptic complexes exhibit a separation of the Ru—C and Ru—N f7-bonding character. It is proposed that the observed preference for cis- over trans- and for fac- over nrer-isomers may arise from the enhanced cr-donating ability of the C atom when it is trans to an N rather than C-donor. ... 

The unusual cage-like structure of S4N4 (7) has evoked continued debate over its electronic structure. The possible existence of bonding interactions between trans-annular sulfur atoms has received particular attention. Extended Huckel CNDO... 

In real tran -polyacetylene, the structure is dimerized with two carbon atoms in the repeat unit. Thus the tt band is divided into occupied tt and unoccupied n bands. The bond-alternated structure of polyacetylene is characterishc of conjugated polymers. Consequently, since there are no partially filled bands, conjugated polymers are expected to be semiconductors, as pointed out earlier. However, for conducting polymers the interconnection of chemical and electronic structure is much more complex because of the relevance of non-linear excitations such as solitons (Heeger, 2001). 

X-Ray irradiation of K2Ni(CN)4 doped into NaCl crystals afforded both nickel(l) and nickel(III) species, Ni(CN)4Cl5 and Ni(CN)4Cl2 which have been characterized by EPR spectroscopy.3067,3068 The nickel(IH) species has been associated with a two cation vacancy. The g values are gy = 2.008, gx = 2.153 and are consistent with a trans octahedral structure. Similar results were obtained by electron (2 MeV) irradiation of K2Ni(CN)4 doped into KC1.3069 In this case two isomers, cis and trans, were identified. 

A considerable number of experiments have shown that symmetrical PMDs in the ground state have an all-trans configuration and are neady planar with practically equalized carbon—carbon bonds and slightly alternating valence angles within the polymethine chain (1,3,5,22,23). This is caused by some significant features of the PMD electron structure. 

The strategies for saddle point optimizations are different for electronic wave functions and for potential energy surfaces. First, in electronic structure calculations we are interested in saddle points of any order (although the first-order saddle points are the most important) whereas in surface studies we are interested in first-order saddle points only since these represent transition states. Second, the number of variables in electronic structure calculations is usually very large so that it is impossible to diagonalize the Hessian explicitly. In contrast, in surface studies the number of variables is usually quite small and we may easily trans-... 

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